Trigger mechanism for firearms



W. C. ROEMER TRIGGER-MECHANISMFOR FIREARMS Earch 24, 1942.

Filed March 28, 1940 5 Sheets-Sheet 1 2% 3M2 w. c. ROEMER ,2 9

TRIGGER-MECHANISM FOR FIREARMS Filed March 28, 1940 5 Sheets-Sheet 2 l, x v n w. c. ROEMER 2,277,561

TRIGGER-MECHANISM. FOR FIREARMS March 1942,

Filed March 28, 1940 5 sheeasug 3 #HNON-FIRING p mN 1U STAGE OVEMENT M 55 "7 52 51/ 58 Non-mm POSITION is STAGE movi 2'39 STAGE MOVEMENT FIRING ON arch 24, 1942.

W. C. ROEMER TRIGGER-MECHANISMFOR FIREARMS 5 Sheets-Sheet 4 Filed March 28, 1940 March 24, 1942. w, c, ROEMER 2,277,561

TRIGGER-MECHANISM. FOR FIREARMS Filed March 28, 1940 5 Sheets-Sheet 5 a I IIuEa-M I, ilm- 3 :9 1% g: ':i| mi 15 ml MUJE Patented Mar. 24, 1942 STATS P QFFHCE TRIGGER MECHANISM FOR FIBS Application March 28, 1940, Serial No. 326,308

10 (llaims.

The present invention relates to improvements in trigger-mechanisms for firearms and more particularly to improvements in trigger-mechanisms primarily adapted for use in conjunction with firearms of the type wherein the hammer or other firing-member is very rapidly moved into cooking position simultaneously with a rapid rearward movement of the breech-bolt or equivalent element under the urge, for instance, of the power developed by a just-fired cartridge.

The present invention contemplates the provision of a firing-mechanism wherein a relatively-deep engagement is effected between the sear and the firing-member and wherein the movement of the sear relative to the firing-memher for releasing the latter is effected at a relatively-slow rate during its initial phase and subsequently at a relatively-rapid rate.

One of the objects of the present invention is to provide a firearm having a superior construction and arrangement of parts whereby the trigger is automatically uncoupled from the sear immediately upon the breech-bolt being unlocked and wherein the means for uncoupling and coupling the said trigger and sear acts to provide an initially-soft and easy trigger-pull followed by a relatively-hard and crisp trigger-pull.

Another object of thepresent invention is to provide a superior trigger-mechanism including retirable -coupling-means normally operativelyinterposed between the trigger and the sear and so constructed and arranged with respect thereto as to transmit the initial movement of the trigger to the said sear at a relatively-slow rate followed by transmission at a relatively-more rapid rate.

A further object of the present invention is to provide a superior trigger-mechanism wherein the functions of providing a two-stage trigger pull are devolved upon means which also discharge the function of a coupler between a trigger and sear.

Fig. 2 is an enlarged view partly in vertical central-longitudinal section and partly inside elevation of the portion of the firearm at and adjacent the trigger-mechanism, the hammer being shown in its cocked position and the tri ger in its normal non-firing position preparatory to the discharge of the firearm;

Fig. 3 is a similar but less comprehensive view showing the parts in the positions which they With the above and other objects in view, as

assume when the trigger is at the completion of its first-stage or soft pull movement;

Fig. 4 is a view corresponding to Fig. 3 but showing the parts in the positions which they assume when the trigger ha completed its second-stage or hard pull movement into its firing position to effect the discharge of the firearm;

Fig. 5 is a view corresponding to Figs. 3 and 4 but showing the parts in the positions which they assume immediately following the initiation of the rearward movement of the action-slide and with the trigger held in its firing position;

Fig. 6 is a view corresponding to Figs. 3, 4 and 5, but showing the parts in the positions which they assume when the breech-bolt and actionslide have been moved rearwardly sumciently to fully retire the hammer and thus permit the sear to be moved upwardly into its cocking position, and with the trigger held in its firing position;

Fig. 7 is a broken horizontal sectional view taken on the line !---'i of Fig. 2;

Fig. 8 is a fragmentary transverse sectional view taken on the line 8-8 of Fig. 2;

Fig. 9 is a fragmentary transverse sectional view taken on the line 99 of Fig. 2;

Fig. 10 is a similar view taken on the line Ill-ill of Fig. 2;

Fig. 11 is a fragmentary transverse sectional view taken on the line ll ll of Fig. 2;

Fig. 12 is a perspective view of the trigger, detached;

Fig. 13 is a perspective view of the sear, detached;

Fig. 14 is a perspective view of the unit comprising the bell-crank-like shifter and the transmitting-member carried thereby;

Fig. 15 is a perspective view of the transmitting-member, detached;

Fig. 16 is a broken perspective view of the rear .portion of the action-slide looking mainly at the underside thereof; and

Fig. 17 is a perspective view of the hammer.

The firearm herein chosen for illustrating the present invention includes a receiver 20, a barrel 2 I a tubular receiver-extension 22, a trigger-plate 23 and a stock 24. The barrel 2| i secured in the usual manner of firearms to the said receiver 20 and extends forwardly therefrom, and the tubular receiver-extension 22 is rigidly secured to and extends rearwardly from-the said receiver and serves to couple the latter firmly to the stock 26.

' The receiver 26 is provided in its interior with a mechanism-receiving chamber 25 in which a breech-bolt 26 is adapted to be tilted and reciprocated by an action-slide 27. The action-slide 21 reciprocates longitudinally of the firearm, and may be moved rearwardly in any suitable manner such, for instance, as by a gas-operated piston, as is shown in my co-pending application, Serial No. 313,650, filed January 13, 1940.

v The reciprocating breech-bolt 26 just above referred to has pivotally coupled to its rear end by means of a pivot-pin 28, the upper end of an operating-link 29, which latter is also pivotally secured at its lower end by a pivot-pin 36 to a cross-head 3| forming a feature of the actionslide 21 before referred to. Brazed, welded or otherwise secured to the respective opposite sides of the cross-head 31 of the action-slide 21, are the rear ends of two parallel spaced-apart sidebars 32-32 constituting part of the said actionslide. The side-bars 32-32 of the action-slide 2? are held in laterally-spaced-apart relationship by the cross-head 3| and extend forwardly therefrom with capacity for longitudinal reciprocating movement therewith.

Extending rigidly rearwardly from the crosshead 3| of the action-slide 21 is a stem 33 bearing atits rear end against the forward end of aspring-plunger 34 (Fig. 1). The said springplunger is mounted with capacity for reciprocating movement in the receiver-extension 22 before referred to and is constantly urged forwardly by a helical bolt-return spring 35 (Fig. l)

The trigger-plate 23 has side walls 36-36 which are laterally-spaced-apart to provide an upwardly-opening longitudinal clearance-groove 31 in the said trigger-plate, which latter may be secured to the underside of the receiver 26 in any suitable manner. Upwardly projecting from the upper edges of the respective side walls 36-35 just referred to, are ears 38-38 (Fig. 9) serving to support the respective opposite ends of a pivotpin 39 mounting a hammer 46 for pivotal movement between the said ears 36-36.

The hammer 46 is formed in its rear face with a longitudinal clearance-groove 41 designed to receive the forward end of a hammer-actuating plunger 42 pivotally secured by a pivot-pin 63 to the said hammer 40. The hammer-actuating pear.

To enable the hammer to andthe forward portion of the hammer-actuating plunger 52 to swing through their desired arcs, the actionslide 21 is provided with a longitudinal clearance-slot 49. The said clearance-slot is formed partly in the stem 33 and partly in the crosshead 3| of the action-slide 2i, and is of suficient length to accommodate the hammer 66 when the same is in its cocked position.

The trigger-plate 23 is formed with a usual integral loop-like trigger-guard 56 which encloses the finger-piece 55 of a trigger 52 carried by the said trigger-plate. The major portion of the trigger 52 is located in the clearancegr00ve 31 of the said trigger-plate 23 and is mounted for pivotal movement upon a pivot-pin 53' extending transversely of .the said trigger-plate with its respective opposite ends supported in the side walls 36-36 thereof, as is shown in Fig. 8. The finger-piece 5! of the trigger 52 extends downwardly through a vertical clearance-slot 56 formed in the said trigger-plate 23 and leading downwardly from the clearance-groove 3? therein to the underside of the said trigger-plate.

The trigger 52 is formed with two laterallyspaced-apart parallel arms 55-55 united adjacent their forwardly-projecting ends by an integral bridge 56, for the purpose as will later ap- The said arms 55-55 also extend upwardly so as to provide the central portion of the trigger 52 with a longitudinal clearancegroove 51 across which the pivot-pin 53 of the trigger 52 extends. Located in the clearancegroove 51 of the trigger 52 is the rear end of a sear 58 mounted upon the pivot-pin 53 just referred to, for independent pivotal movement with respect to the said trigger 52.

The sear 56 extends forwardly between the arms 55-55 of the trigger 52 with its forward portion passing beneath the bridge 56 of the said trigger, as is clearly shown in Figs. 2 to 6 inclusive. Formed on the upper edge of the sear 58 about midway of its length is a forwardly-facing cocking-shoulder 59 adapted to engage a relatively-deep rearwardly-facing cocking-abutment The sear 58 by the engagement of its cocking-shoulder 59 with the cocking-abutment 66 of the hammer 46 serves plunger 42 includes a rearwardly-extending.

spring-guiding stem 44 mounted at its rear for sliding movement in a transversely-extending abutment member 45 located in the clearancegroove 31 of the trigger-plate 23 and pivotally the abutment-member and the shoulder All of the plunger 42, to constantly urge the hammer 46 forwardly to strike a firing-plunger 33 carried by the breech-bolt 26 to effect the discharge of a cartridge.

to releasably maintain the said hammer in its cocked position against the tension of the hammer-spring 46 until such time as the cockingshoulder 59 is moved downwardly out of engagement with the cocking-abutment 60 of the hammer 46 by the actuation of the trigger 52, all as will more clearly hereinafter appear.

Immediately to the rear of its cocking-shoulder 59, the sear 58 is formed on its upper edge with a concave arcuate abutment 62 adapted to be engaged with the convex arcuate outer face of a lug 63 forming that portion of the hammer 46 immediately forwardly of the cocking-notch 60. The arcuat'e outer face of the lug 63 is concentric with the center 'of the pivot-pin 39 of the hammer 46 and serves when engaged by the arcuate abutment 62 of the sear 56, to retain the said .sear in its depressed or hammer-releasing position, for the purpose and in a manner as will hereinafter appear.

The sear 56 is provided intermediate the pivot-pin 53 and the cocking-shoulder 53 thereof with a downwardly-opening spring-pocket 65 in which is located the upper portion of a helical sear-spring 65 having its lower end seated against the adjacent portion of the bottom of the clearance-groove 31 in the trigger-plate 23. The sear-spring 85 exerts a constant but yielding efiort to swing the sear 58 upwardly into position to interpose its cocking-shoulder 59 in the path of movement of the cocking-abutment 60 of the hammer 80. At its forward end the sear 58 is formed with a downwardly-and-forwardlyextending finger 68 which normally is positioned over and in registration with a notch 61 provided in a cylindrlcally-contoured safety-slide 58.

The safety-slide 58 is mounted for axial shifting movement in a passage 89 extending transversely of the trigger-plate 23 in the portion thereof adjacentthe forward portion of the space enclosed by the trigger-guard 58 of the said trigger-plate, as is clearly shown in the drawings. The safety-slide 58 is adapted to be axially shifted in the passage 89 into either its safe position or firing position as is usual with safety devices. It will be understood that by axially shifting the safety-slide 68 into its safe" position (indicated by broken lines in Fig. 11), the notch 81 therein will be moved out of registration with the finger 55 of the sear 58 to thus bring a peripheral portion NJ of the said safetyslide beneath the finger 68 of the said sear 58 to thus prevent the said sear from being moved downwardly for the release of the hammer 40. By shifting the said safety-slide into its firing? position, the notch 61 therein will be in the position shown by full lines in the drawings, and the sear 58 may be moved downwardly in a manner as will hereinafter appear, thus entering the finger 66 thereof into the notch 61 of the said safety-slide without interference thereby when the trigger 52 is actuated to effect the discharge of the'firearm.

Intermediate the cocking-shoulder 59 and the finger 88 of the sear 58, the said sear is formed with a longitudinal clearance-slot H which substantially underlies the brid e 58 of the trigger 52, as is clearly shown in Figs. 2 to 6 inclusive.

Forwardly of the hammer 48 the trigger-plate 23 pivotally carries a shifter 72 of bell-cranklike form. The shifter 12 is mounted for pivotal movement on a pivot-pin 13 extending transversely of the said trigger-plate 23 across the upper forward portion of the clearance-groove 81 therein and is supported at its respective opposite ends in the respective side walls 3636 of the said trigger-plate, as is clearly shown in Fig. 11. The shifter 72 has a depending-arm M which is formed in its lower end with a longitudinal clearance-notch 15 resulting in the formation of laterally-spaced-apart ears 15-45.

The clearance-notch i just above referred to receives the forward or inner end of a horizontally-arranged pivotal transmitting-member 11 which is mounted for free rocking movement relative to the shifter 12 upon a pivot-pin 18, the respective opposite ends of which latter are supported in the ears |8l8 of the arm M of the said shifter. The transmitting-member 11 extends rearwardly substantially horizontally and has a relatively-narrow rear portion I9 normally located over the clearance-slot 'II in t e sear 58 and beneath the under face of the bridge 58 of the trigger 52, as is clearly shown in Fig. 2.

The outer or rear end of the rear portion 19 of the transmitting-member H is formed with an upwardly-extending first-stage actuatingnose 80 normally in engagement with the under face of the bridge 58 of the trigger 52, as clearly shown in Fig. 2. The said bridge may be said to constitute the first stage actuating-abutment of the trigger 52. Intermediate its actuating-nose and its pivot-pin 18, the said transmitting-member 11 is formed on its under face with a downwardly-extending sear-actuating lug 8| which normally is in engagement with an upwardly-facing actuating-surface 82 provided adjacent the forward or free end of the sear 58.

It may here be noted that the arms 55-55 of the trigger 52 are formed attheir forward ends adjacent the respective upper edges thereof and forwardly of the bridge 56 with two laterallyspaced-apart second-stage actuating-abutments 83-83. The actuating-abutments 83 83. of the trigger 52 project inwardly toward each other from the inner faces of the respective arms 55- 55 of the said trigger and normally overlie the relatively-broad portion 84 of the upper faceof the transmitting-member 11 immediately forwardly of the relatively-narrow rear portion 19" thereof. The said portion 84 is engageable by the second-stage actuating-abutments 83-83 and may, therefore, be properly termed the second-stage" abutment of the transmitting-member 11.

Returning to the shifter 12, it will be noted that the same is provided immediately forwardly of the pivot-pin 13 with two laterallyspacedapart upwardly-and-forwardly-inclined springpockets 8585 in which are located the lower portions of two helical springs 88-8E (Fig. '7) which thrust against the adjacent portion of the trigger-plate 23. The shifter 12 also includes a horizontal arm 81 which carries at its rear end a relatively-long cam-pin 88 extending transversely through the said arm 81 with each of its respective opposite ends normally disposed in the adjacent one of two clearance-notches 89-89 respectively formed in the under edge of the adjacent rear portions of the side bars 3232 of the action-slide 27, when the latter is in its forward position.

The springs 8586 above referred to constantly urge the shifter 12 to turn in a clockwise direction as viewed in the drawings, to yieldingly maintain the rear or outer portion of the transmittingmember 11 interposed between the bridge 55 of the trigger 52 and the sear 58, as is shown in Figs. 2, 3 and 4. The springs 85-86 also serve to urge the opposite ends of the cam-pin 88 respectively upwardly into the clearance-notches 89--89 of the action-slide 21 for engagement by forwardly-and-downwardly-inclined uncouplingcams Elli -90, respectively forming the forward wall of each of the two clearance-notches 89-89.

To hold the trigger 52 in its normal non-firing position, the said trigger is formed adjacent its finger-piece 5| with an upwardly-and-rearwardly-inclined spring-pocket 9| opening through the rear upper edge thereof and receiving a springplunger 92 having a guide-stem 93 encircled by a helical trigger-spring 94. One end of the trigger-spring 98 thrusts against the end-wall of the spring-pocket 9| while the opposite end thrusts against the adjacent face of the springplunger 92 to thus hold the said spring-plunger inseated engagement with the adjacent portion of the trigger-plate 23 and thus hold the trigger 52 in its normal or non-firing position.

As will be apparent from the accompanying drawings and the present description the cocklug-shoulder 59 of the sear 58 has a relativelylong or deep engagement with the cocking-abutment 60 of the hammer 40 just prior to the trigger being pulled. This depth of engagement'may, for example, be .05 inch. The cocking-shoulder 59 of the sear 58 is disengaged from the cookingabutment 68 of the hammer 48 in two stages, namely, a first stage and a second stage. During the first-stage movement the trigger-pull may be characterized as soft or light during which referredto, the finger-piece of the trigger must be moved a relatively-great distance to efiect a relatively-small degree of movement of the sear The second-stage movement of the sear 58 is accompanied by what may be termed a hard or. heavy pull of the trigger, sometimes referred to as-a crisp pull. This second-stage move-* ment ofthe sear effects the complete disengagement of its cocking-shoulder 59 from the cockingabutment 68 of the hammer 48 and causes the said sear to move more rapidly relative to the trigger-movement than was the case during the first-stage movement referred to. 1

For the purpose of description let it be assumed that the firearm is loaded and that the hammer 48 is cocked and the associated parts are in their respective positions in readiness for the discharge of the firearm, as shown particularly well in Figs. 1 and 2. Under these conditions the breach-bolt 26 is fully in its breech-closing position and the action-slide 2'! is in its full forward position. The safety-slide 68 will, when the firearm is in readiness for firing, be in its firing position, i. e., in such position that its notch 61 is in full registration with the finger 65 of the sear 58.

If rearward draft is now applied to the fingerpiece 5! of the trigger 52 to rock the said trigger clockwise about its pivot-pin 53 against the tension of the trigger-spring 94, the said trigger will be first swung through a first-stage. movement from the position in which it is shown in Fig. 2 to that in which it is shown in Fig. 3. The rocking of the trigger 52 through its first-stage movement will occur under conditions wherein the advantages of leverage are in favor of the trigger to provide a relatively-long light or soft triggerpull, as will now more fully appear.

The clockwise rocking movement of the trigger 52 as just above referred to, will swing its forward end downwardly to cause the bridge 55 thereof to correspondingly move the first-stage actuating-nose 88 of the transmitting-member Ti downwardly and hence similarly swing the said transmitting-member. The downward swinging movement of the transmitting-member H as just described will move the rear portion 19 thereof downwardly and will cause the actuating-lug 8! of the transmitting-member l? to press against the actuating-surface 82 of the sear 58 to concurrently move the outer or forward end of the said sear downwardly against the tension of the sear-spring 65. This movement of the sear will withdraw the cocking-shoulder 58 thereof slightly more than halfway toward its complete disengagement from the cocking-abutment 68 of the hammer 48. The parts will now have reached the positions in which they are shown in Fig. 3.

It will be noted that during the first-stage movement the movements of the bridge 58 of the trigger 52 and the first-stage actuating-nose 88 of the transmitting-member T1 are greater than the movement of the actuating-lug 8| of the said transmitting-member since the said actuatingsear 58.

lug is located intermediate the said bridge and actuating-nose and the pivot-pin 18.

The relative positions of the bridge and actuating-nose 80 with respect to the pivot-pin 18 of the transmitting-member 11 results in a leverage requiring a. relatively-light or soft triggerpull to swing the sear 58 downwardly through its first-stage movement, as above described. It will also be understood that due to the leverage just above described a relatively-long triggerpull is required to eflect a relatively-short swinging movement of the sear 58.

The parts will now occupythe positions in which they are shown in Fig. 3 with the bridge 56 and the second-stage actuating-abutments 83-83 of the trigger'52 respectively in engagement with the first-stage actuating-nose 38 and the second-stage abutment-portion 84 of the transmitting member 'I'l.v

. When the trigger 52 has been moved through to the completion of its first-stage movement of relatively-light or soft pull as just above described, there will be an apparent tighteningup, so to speak, of the trigger-pull. In this manner, the user of the firearm may accurately gauge the point at which the hammer 48 will befully released by'the sear 58.

After the parts have assumed the positions shown in Fig. 3, additional swinging movement of the trigger 52 will cause the second-stage actuating-abutments 83-83 of the said trigger to press downwardly upon the second-stage abutment-portion 84 of the transmitting-member Ti and thus further rock the said transmittingmember downwardly to cause the rear portion 19 thereof to enter into the clearance-slot H of the This rocking movement of' the transmitting-member 11 will cause the sear-actuating lug 8| thereof to further depress the sear 58 against the tension of the sear-spring to move the cocking-shoulder 59 thereof downwardly to completely disengage the said cocking-shoulder from the'cocking-abutment 68 of the hammer 50,

' thus releasing the said hammer to the action of its hammer-spring 58 and thus discharge the firearm.

The sear, trigger and transmitting-member win now have assumed the positions in which they are shown in Fig. 4. In this figure the hammer is shown as moved part way up into position to discharge the firearm.

It will be apparent that the engagement of the second-stage actuating-abutments 83-83 of the trigger 52 with the second-stage abutment-portion 84 of the transmitting-member 1'! is closer to the pivot-pin 78 of the latter than the previous engagement of the bridge 56 of the trigger 52 with the first-stage actuating-nose 80 of the transmitting-member TI. This shifting of the point of contact between the trigger 52 and the transmitting-member 11 results in a relative increase of movement of the transmitting-member Tl relative to the said trigger and hence imposes I additional load thereon. The relative increase of movement of the transmitting-member as just described, compels a lesser movement of the trigger 52 to now effect the movement of the sear 58 through its second stage and hence requires greater pressure to be exerted upon the trigger 52 has completed its first-stage movement, the point of contact between the said trigger and the transmitting-member H is moved forwardly closer to the pivot-pin of the said transmittingmember and, therefore, requires the exertion of greater pressure upon the finger-piece of the said trigger in order to effect the full release of the hammer 48 by the sear 58. This increase in pressure will be readily apparent to the user of the firearm, thus giving indication that the trigger has been moved to a point where a slight further rearward draft on the said trigger will cause the complete release of the hammer.

After the completion of the first-stage triggerpull, if the user should relax the pressure upon the trigger the angular relationship of the cocking-shoulder 59 and the cocking-abutment 88 is such that the sear 58 will reassume its initial position shown in Fig. 2, to thus insure a safe searengagement when the firearm is carried in a cooked and loaded condition.

The withdrawal of the cocking-shoulder 58 of the sear 58 as above described will enable the hammer 48 to be rapidly swung in a clockwise direction into the position indicated by broken lines in Fig. 4, under the urge of the hammerspring 88. The hammer 88 near the completion of its clockwise turning movement under the urge of the hammer-spring 48 will sharply strike the ,rear exposedend of the firing-plunger 88 to snap the latter forwardly to discharge the cartridge contained in the cartridge-chamber of the firearm, in a manner well understood in the art.

When the trigger 52 is actuated as above described, to effect the downward movement of the sear 58 for the release of "the hammer 88, the finger 68 of the said sear is entered into the notch 5! of the safety-slide 58 when the said safetyslide is in its firing position, as shown by full lines in Fig. 11. In this manner the safety-slide 58 is prevented from being axially shifted into its so-called safe position until such time as the sear 58 is again in its upper position.

When the sear is in its depressed or hammerreleasing position, and the hammer 58 swings in a clockwise direction to effect the discharge of the firearm, the lug 53 of the said hammer will override the arcuate abutment 82 of the said sear 58. With the lug 68 of the hammer 88 actuated over the arcuate abutment-82 of the sear 58 as shown in Figs. 4 and 5, the sear 58 will be prevented from swinging upwardly under the urge of the sear-spring 85 until such time as the hammer 48 is again substantially-fully retired.

It will be apparent from the foregoing that the sear 58 is held in its depressed position by the hammer 48 during the major portion of the latters swinging movement in both clockwise and counterclockwise directions. The said sear is released for upward movement only when the said hammer is in its retired position as shown in Figs. 2, 3 and 6.

Following the discharge of the firearm, the

rearward movement of the action-slide 21 will effect the unlocking and rearward travel of the tilting and reciprocating breech-bolt 25 to cause the ejection of the just-fired cartridge. Immediately at the start of the rearward movement or travel of the action-slide 21, the uncouplingcams 9888 of the said action-slide will respectively engage the respective opposite ends of the cam-pin 88, now located in their respective clearance-notches 88--89. The uncoupling-cams 88-88 will force the cam-pin 88 downwardly to thus swing the shifter 12 in a counterclockwise direction .against the tension of the springs 88-86 from the positions in which it is shown in Figs. 2, 3 and 4 into the positions in which it is shown in Figs. 5 and 6.

The counterclockwise movement of the shifter 12 as above described, will swing the lower end of the depending-arm M of the shifter I2 forwardly to thus correspondingly shift the transmitting-member 1! to remove the first-stage actuating-nose 88 thereof from beneath the bridge 55 of the trigger 52. The described shifting movement of the transmitting-member 11 will also movethe abutment-portion thereof forwardly out from beneath the second-stage actuating-abutments 83-83 of the trigger 52, thus enabling the narrow rear portion 18 of the said transmitting-member to be moved upwardly between the said 'actuating-abutments. The forward shifting of the transmitting-member H as just described, will uncouple the trigger 52 and the sear 58 and will permit the sear-spring 65 to assert itself at the appropriate time to swing the sear 58 upwardly into position to enable its cocking-shoulder 58 to be re-engaged by the cocking-abument 68 of the hammer 40 when the said hammer is swung into its cocked position by the rearward movement of the action-slide 21.

The hammer 40 is swung into its cocked position when the action-slide 21 moves rearwardly, by a portion of its cross-head 3| which engages the forward face of the hammer 48 to swing the said hammer in a counterclockwise direction against the tension of the hammer-spring 45.

During all but the initial rearward travel of the action-slide 21, the respective opposite ends of the cam-pin 88 are in engagement with the respective lower edges of the side-bars 32-32 of the action-slide 21. This engagement temporarily prevents the shifter 72 from again assuming the position in which it is shown in Figs. 2, 3 and 4,-and thus serves to hold the transmitting-member I1 out from between the trigger 52 and the sear 58, as shown in Figs. 5 and 6, until such time as the clearance-notches 88-89 of the action-slide 21 are again respectively brought into registration with the opposite ends of the cam-pin 88 by the full return movement of the action-slide 21.

By preventing the transmitting-member 17 from entering the space between the trigger 52 and the sear 58 until such time as the actionslide 21 is fully returned to its forward position, the sear 58 is rendered immune during this time interval against'being held down or again being forced downwardly by any movement of the trigger 52. It will be understood that with the transmitting-member ll withdrawn from between the trigger 52 and the sear 58 as shown in Figs. 5 and 6, said sear 58 is free to move upwardly under the urge of the sear-spring 65 immediately following the complete actuation of the trigger 52.

With the parts in the positions shown in Fig. 6, the rear end. of the transmitting-member I1 is prevented from overriding the bridge 56 when the action-slide 2'! moves forwardy into position to release the shifter 12. This is accomplished by the engagement of the rear face of the said transmitting-member T! with the forward face of the bridge 58 of the trigger 52, until such time as the said trigger is released, whereupon the bridge 58 will slide upwardly with respect tc the said transmitting-member to a degree sufficient to permit the latter member to snap under the said bridge. 'The rear end of the transmitting-member is prevented from rising with the said bridge by the limiting effect of the upper wall of the notch in which the forward end of the said transmitting-member is mounted.

From the foregoing, it will be apparent thatsubstantially immediately following the initiation of the rearward movement of the action-slide 2l,'the shifter I2 is so moved as to render the transmitting-member ll inoperative until such time as not only has the said action-slide been returned to its full forward position but rearward draft upon the trigger 52 has been relaxed. In this manner, the sear 58 is freed for upward movement immediately upon the initiation of the rearward movement of the action-slide 21 following the discharge of the firearm so that the hammer Ml will be cocked regardless of what position the trigger may be in. Furthermore, the next succeeding discharge of the firearm is also prevented until such time as the operator of the firearm has relaxed rearward draft upon the trigger 52.

It will be apparent from the foregoing that the arrangement of parts is such as to prevent the action-slide in the event of damage to or the jamming of the trigger mechanism from disengaging the sear from the hammer upon the rearward movement of the said action-slide. It will be noted that as the action-slide moves rearwardly, it institutes a forward movement of the transmitting-member ll which is substantially alternately operatively-couples and -uncouples the said sear-member and the said trigger-member, the said transmittingmember being constructed and arranged to be sequentially engaged with the first-stage actuating-abutment and the second-stage actuating-abutment upon the aforesaid pivotal member so provided; and means movable in conjunction with the said breech-bolt for shifting the said transmitting-member.

2. A firearm of the multiple-stage trigger-pull type, including in combination: a movable breech-bolt; a firing-member; a pivotal searmember releasably holding the said firing-member in its cocked position; a pivotal trigger-member for shifting the said sear-member into position to release the said firing-member; one of the said pivotal members being provided with a first-stage actuating-abutment and a secondstage actuating-abutment respectively located at different distances from the pivot-point of such pivotal member; means for transmitting the movement of the said trigger-member to the said sear-member at two speed-ratios and including a pivotal transmitting-member mounted in the firearm-structure also with capacity for bodily movement into and out of positions wherein the said transmitting-member alternately operative- .ly-couples and -uncouples the said sear-member parallel with the surfaces between which it is provided. By devolving the function of providing a multiple stage trigger-pull upon a member such as the transmitting-member 71 which also discharges the function of operatively coupling and uncoupling the sear and trigger, a maximum degree of simplicity and reliability is effected.

The invention may be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention, and the-present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.

I claim:

'1. A firearm of the multiple-stage trigger-pull type, including in combination: a movable breech-bolt; afiring-member; a pivotal triggermember; a pivotal sear-member; one of the said pivotal members being provided with a first-stage actuating-abutment and a second-stage actuating-abutment respectively located at different distances from the pivot-point of such pivotal member; means for transmitting the movement of the said pivotal triggeremember to the said pivotal. sear-member at two speed-ratios and including a transmitting-member mounted in the firearm-structure and movabl into and out of positions wherein the said transmitting-member and the said trigger-member, the said transmitting-member being constructed and arranged to engage with both actuating-abutments of the pivotal member so provided; and means movable in conjunction with the said breech-bolt for bodily moving the said transmitting-member into one of its two positions referred to.

3. A firearm of the multiple-stage trigger-pull type, including in combination: a movable breech-bolt; a firing-member; a pivotal triggermember; a pivotal sear-member; one of the said pivotal members being provided with a firststage actuating-abutment and a second-stage actuating-abutment respectively located at different distances from the pivot-point of such pivotal member; means for transmitting the movement of the said pivotal trigger-member to the said pivotal sear-member at two speed-ratios and including a transmitting-member mounted in the firearm-structure and movable into and out of positions wherein the said transmittingmember alternately operatively-couples and -uncouples the said sear-member and the said trigger-member, the said transmitting-member being constructed and arranged to be sequentially engaged with the first-stage actuating-abutment and the second-stage actuating-abutment upon the aforesaid pivotal member so provided; a shift= ing-member operatively connected to the transmitting-member of the aforesaid means for shifting the same into and out of position to operatively couple the said trigger-member and the said sear-member; and means movable in conjunction with the said breech-bolt for actuating the said shifting-member to move the said transmitting-member out of position to operativelycouple the said trigger-member to the said searmember. i

4. A firearm of the multiple-stage trigger-pull type, including in combination: a movable breech-bolt; a firing-member; a pivotal searmember releasably holding the said firing-member in its cocked position; a pivotal trigger-member for shifting the said sear-member into posi tion to release the said firing-member; one of the said pivotal members being provided with a first-stage actuating-abutment and a secondstage actuating-abutment respectively located at difi'erent distances from the pivot-point of such pivotal member; means for transmitting the movement of the said trigger-member to the said sear-member at two speed-ratios and including a pivotal transmitting-member mounted in the firearm-structure also with capacity for bodily movement into and out of positions wherein the said transmitting-member alternately operatively-couples and -uncouples the said sear-member and the said trigger-member, the said transmitting-member being constructed and arranged to engage with both actuating-abutments of the pivotal member so provided; a shifting-member operatively connected to the pivotal transmitting-member of the aforesaid means for bodily shifting the same into and out of position to operatively-couple the said sear-member and the said trigger-member; and means movable in conjunction with the said breech-bolt for actuating the said shifting-member to bodily move the said transmitting-member out of position to operatively-couple the said pivotal trigger-member and the said pivotal sear-member.

5. A firearm of th multiple-stage trigger-pull type including in combination: a movable breech-bolt; a firing-member; a sear releasably holding the said firing-member in its cocked position; a pivotal trigger for shifting the said sear into position torelease the said firing-member and provided with a first-stage actuatingabutment and a second-stage actuating-abut-' ment located a greater distance from the pivotpomt or the trigger than is the said first-stage actuating-abutment; a transmitting-member constructed and arranged to be sequentially engaged first by the first-stage actuating-abutment and then by the second-stage actuating-abutment of the said pivotal-trigger, the said transmitting-member being constructed and arranged to be moved into and out of positions for alternately operatively-coupling and -uncoupling the said sear and trigger; and means movable in conjunction with the said breech-bolt for shifting the said transmitting-member into one of its two aforesaid positions.

6. A firearm of the multiple-stage trigger-pull type, including in combination: a movable breech-bolt; a firing-member; a sear releasably holding the said firing-member in its cocked position; a pivotal trigger for shifting the said sear into position to release the said firing-member and provided with a first-stage actuatingabutment and a second-stage actuating-abutment located a greater distance from the pivotpoint of the trigger than is the said first-stage actuating-abutment; a transmitting-member constructed and arranged to be sequentially engaged first by the first-stage actuating-abutment and then by the second-stage actuatingabutment of the said pivotal-trigger, the said transmitting-member being constructed and arranged to be moved into and out of position for alternately operatively-coupling and -uncoupling the said sear and trigger; a shifting-member operatively connected to the said transmittingmember for shifting the same into and out of positions to operatively-couple'the said sear and the said pivotal-trigger; and means movable in conjunction with the said breech-bolt for moving the said shifting-member to cause the same to move the said transmitting-member out of position to operatively couple the said pivotaltrigger and the said sear.

7. A firearm of the multiple-stage triggerpoint of the said pivotal-trigger than is the said first-stage actuating-abutment thereof; means for transmitting the movement of the said trigger-member to the said sear-member at two speed-ratios and including a transmitting-member mounted in the firearm-structure with capacity for both pivotal movement and bodily movement, the said transmitting-member being bodily movable into and out of positions wherein the same alternately operatively-couples and -uncouples the said sear-member and the said trigger-member, the said transmitting-member being" constructed and arranged to be successively engaged by the first-stage and the second-stage actuating-abutments of the said trigger-member; and means, movable in conjunction with the said breech-bolt for bodily shifting the said transmitting-member.

8. A firearm of the multiple-stage trigger-pull type, including in combination: a, movable breech-bolt; a firing-member; a pivotal searmember releasably holding the said firingmember in its cocked position; a pivotal triggermember for shifting the said sear-member into position to release the said firing-member and provided with a first-stage actuating-abutment and also a second-stage actuating-abutment located more remote with respect to the pivotpoint of th said pivotal-trigger than is the said first-stage actuating-abutment thereof; means for transmitting the movement of the said trigger-member to the said sear-member at two speed-ratios and including a transmitting-member mounted in the firearm-structure with capacity for both pivotal movement and bodily movement, the said transmitting-member being bodily movable into and out of positions wherein the same alternately operatively-couples and -uncouples the said sear-member and the said trigger-member, the said transmitting-member being constructed and arranged to be successively engaged by the first-stage and the secondstage actuating-abutments of the said triggermember; a pivotal shifting-member operatively connected to the said transmitting-member; and means movable in conjunction with the said breech-bolt for turning the said pivotal shiftingmember to bodily shift the said transmittingmember out of position wherein the said transmitting-member operatively-couples the said trigger-member and the said sear-member.

9. A firearm of the multiple-stage trigger-pull type, including in combination: a movable breech-bolt; a firing-member; a sear releasably holding the said firing-member in its cocked position and formed with an actuating-abutment and with a clearance-opening adjacent thereto; a trigger for shifting the said sear into position to release the said firing-member; means for transmitting the movement of the said trigger to the said sear at two speed-ratios and including a pivotal transmitting-member engageable with the actuating-abutment of the said sear and constructed and arranged to be tilted into the clearance-opening thereof, the said transmitting-member being constructed and arranged iformovements into and. out of position to operatflvely-couple and -uncouple the said seer and trigger; and means movable in conjunction with the said breech-bolt for shifting the said trans refitting-member,

it). A firearm of the multiple-stage trigger- ;ouii type, inctuding in combination: a movable breech-bolt; e firing-member; a sear releasably holding the said fling-member in its cocked position end formed with em actuating-abutment and. with a clearance-opening adjacent thereto; a trigger for shifting the said sear into posi tion to release the said firing-member; means for transmitting the movement of the said, triggee to the said seer at two speed-ratios and in= 15 t0 operativeiy-couple and -uncoup1e the said seer and trigger; a, pivotal shifting-member operattively connected to the said transmitting-memher for moving the same; and means movable in conjunction with the said breech-bolt tor turning the said pivotal shifting member to cause the same to retire the said transmittingmemher out of position wherein the same operatively-coupies the said sear and the said trigger. 

